Electromagnetic piano.



' G. BREED.

ELEcmoMAGNEnc PIANO.

APPLICATION FILED MAR. 20, 1912.

Patented Mar. 7, 1916.

2 SHEETS-SHEET l.

G. BREED.

ELECTROMAGNETIC PIANO.

APPLICATION FILED MMI` 2o, I9I2.

2 SHEETS-SHEET 2.

fw I ff UNITED STATES PATENT OFFICE.

GEORGE BREED, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR T0 LYRACHORDCOMPANY, A CORPORATION OF NEW YORK.

ELECTROMAGNETIC PIANO.

State of Pennsylvania, have invented a newl and useful ElectromagneticPiano, of which 'the following is a specification.

This invention is an electromagnetic musical instrument having improvedtone producing and sustaining mechanism combined in a. hammer pianoadapted to be operated manually, by means of the usual keys, ormechanically, by means of the usual pneumatic mechanism. ,i

Characteristic improvements of my invention reside in its means whereby.the performer is able, at will, to draw from the instrument the tonesproduced by the hammers alone, sustained tones of the desired volumeproduced by the electro-magnets alone, or the desired blending of suchtones either by the operationof the keys or the pedals of theinstrument.

The improved features of my invention are fully disclosed in thefollowing description and the accompanying drawings in illustrationthereof. v

On the accompanying drawings, Figure 1 is a sectional elevation of apiano embodying my invention. Fig. 2 is a diagrammatic, part sectional,View illustrating a unit of my improvements, and Fig. 3 is a detail viewillustrating features of the mechanism for varying the electro-magneticaction. i The mechanism, as illustrated in the drawings, comprises a setof the usual musical strings 1, hammers 2, and dampers 3 carried by therail 4, wippens 5 fulcrumed with relation to the rail 4, abstracts 6,jacks 7 and springs 8 through which the wippens ,5 act upon the hammers2 and dampers 3,

respectively, keys 9 which act through the abstracts 6 to rock thewippens 5, and flexible fingers 10 'whichcan be rocked to operate thewippens 5 by rods 11. through the action thereon of\ bellows orpneumatics 12, which are connected to the Wind-trunk 13 fromwhich theair is exhausted by' the bellows 14 operated by treadles.

The wind-trunk 13 is provided with a Specification of Letters Patent.

.rail and magnets thus'forming a unitary- Patented Mar.'7, 1916.

Application filed March 20, 1912. Serial N o. 684,922.

reservoir or storer 130 and is connected by passages to valve boxes 131on which the pneumatics 12 are carried. The pneumatics are called intooperation from a perforated note-sheet 132 which is drawn from a musicspool 133 over a tracker bar 134 and wound on a take-up spool 135. Theseparts are arranged so that the instrument can be played eitherautomatically by the pneumatic mechanism, or manually by the keys 9.

Arranged in front of each string which is to be operatedelectro-magnetically, is an electro-magnet 15 (Fig. 2) made U-shaped andprovided with a coil 15 preferably only on one arm, which arm hasthreaded therethrough a metallic core 15 by which the relation of theend of the pole can be adjusted relatively to the string. Theelectromagnets are supported in a rail 16 by embedding them ininsulating material 16', the

structure which can be easily placed in position, in which individualadjustments can be made, and by which construction the parts are notliable to derangement.

Each magnet is in a circuit comprising a conductor 17 (containing aswitch 18) connected with a'battery 19, or other source of electricalenergy, a conductor 2O connecting the battery with a conductor 21 havingcoils 21', a contact 22 engaged to the coils 21', a resilient conductor23 having coils 23, a contact 24 engaged in the coil 23 and adapted toengage the contact 22, a tine wire 25 connecting the conductor 23 withthe end of a resilient conducting loop 26, a conductor 27 connecting theloop 26 with the resilient contact 28, a resilient contact 29 with whichthe contact'28is adapted to engage and conductor 30 connecting thecontact 29 with the electro-magnet 15 4and thus completing theV tacts 32and connected at its other end with a resilient contact 39, a conductor40, connecting the conductor 17 with a resilient contact 41, aresistance coil 42, connecting the contact-,'41 with a resilient contact43,

a resistance coil 44, connecting the contact l 43 with a resilientcontact 45, and a movable vbridge 46 adapted for connecting the contacts39, 41, 43 and 45, for cutting out the contacts 41 and 43 in successionso as to cut in the resistances 42 and 44 in succession and for breakingcommunication between the contacts 39 and 45 so as to cut out the shuntcircuits.

The contacts 39, 41, 43 and 45 are fixed to ablock 47 which is providedwith an arm 47 (Fig. 3) and which is connected by ahinge 48 to a support49. A spring 49 acts on the block to hold the contacts in engagementwith the bridge 46, and' a rod 50, operated by a button 50, acts on thearm 47 to effect the withdrawal of the contacts from the bridge and cutout the shunt circuits. The bridge 46 is fixed on a cylinder 51 which issecured on a journaled shaft 52. The latter acts through a crank 53 andlink 54 on an-arm 55 by which the hammer rest rail 56 is turnedon itsbearings 57 An arm 58 is fixed on the shaft 52 and connected withl aspring 59, secured to a fixed part, whereby the connected parts arenormally held in the position shown. A rod 60, provided with a button60, acts on an arm 61 which is fixed to the shaft 52 eccentrically tothe cylinder 51, and a rod 62, operated by pedal 63, acts on the pin 64mounted on a crank arm xed to the shaft 52 and also eccentric to thecylinder 51. The shaft 52 may acf cordingly be moved either by means ofthe button 60 or by the pedal 63 to change the positin of the bridge 46relative to the contacts 39, 41, 43 and 45, and such movement of theshaft through the arm 53 and the link 54 will simultaneously change theposition of the hammer rest rail 56. `When the shaft 52 is moved by thebutton 60 or by the pedal 63 to increase the resistance in the shuntcircuit and thus increase the intensity of the electromagnetic effect,the arm 53 draws the rod 54 downward, thus retracting the hammer restrail 56. This permits a longer stroke of the hammers which is the usualand well known method of mechanically increasing the intensity of theeffect of the hammer actions. Hence the stroke ofeach hammer and theelectromagnetic eect on the string operated therebyv are correlated.

rIhe pulsators, (each comprising the parts 21, 22, 23, 24, 25 and 26),are supported by a rail comprising sections 65 and 65y (preferably ofwood), between which the parts 21 are clamped and properly insulated,the,

spring 23 being connected by bracket 66 to the part 65 and the spring 26being connected to the part 65 by the adjusting screw 67, whereby thetension of the wire 25 and the consequent regulation of the pulsatorsac- '1 and pulsating string 71, the end of the string 74 being securedto a button 75 which is adjustable and held by friction on the string71.

0f course, there is an electro-magnet, a y

circuit. controlling device, and a pulsator for each string which is tobe operated electromagnetically, and the conductors can be convenientlyarranged by wiring the set of mag-- nets in multiple arc from po-int a,connecting each magnet to the member 29 of its circuit controllingdevice by an additional conductor 30, connecting each member 28 of eachcircuit controlling device to its pulsator by an individual conductor27, and by connecting the pulsators to a common return conductor b.

It also will be noticed that when the abstract is elevated, the contacts28 and 29 are first brought together and then the contact 29 is broughtagainst the contact 32. By this arrangement, the full current will besent for an instant through the electro-magnet and pulsatorbefore theshunt circuit is closed, whereby the pulsator will be started in fullvibration at the beginning of the operation.

ylln operation, when the switch 18 is open, the electro-magnetic actionis disconnected and the tones are produced by the usual hammer actions,either manually or pneumatically. thebridge' 46 in position for directlyconnecting the contacts of the circuits controlled thereby, uponelevating an abstract (whether by the direct action of a keyv 9 or theindirect With theswi'tch 18 closed and action of a pneumatic 12)O theblock 35 will effect the engagement of the contact 28 with the contact29, thereby closing the main circuit containing the electro-magnet 15and battery 19.

The electro-magnet being excited by the current nowflowing therethrough,the string current, and the desired phase relation beu tween thevibration of the string 1 and the pulsations of the current beingeffected by the adjustment of the string 71.

I f an abstract be elevated, so as to effect additionally the engagementof the contacts 29 and 32 while the contacts 39 and 4l are connected bythe bridge 46, part Iof the current otherwise passing through thecorresponding electro-magnet will flow through the shunt circuitcontaining these contacts, the electro-magnet receiving a reducedportion of the current, (depending upon the shunt circuits resistance),and the string 1 consequently producing a softer tone. As the cylinder51 can be turned so as to disengage r engage the bridge 46 with relationto the contacts 41 and 43 and thus cut in or out one or both of theresistances 42 and 44, the current passing through theshunt circuit andthe electro-magnet can be varied in inverse ratio with resultingvariation in the tone. by pushingl the button so as to tilt the block47, the contacts carried thereby are disengaged from the bridge, theshunt circuit is broken, the maximum current is passed through theelectro-magnet and the maximum tone is produced.

The buttons are used principally when the instrument is being operatedautomatically through the pneumatic mechanism. During this operation,the full or most powerful electro-magnetic effect can be obtained bypressing down upon the button 50', while a graduated effect can be0btained by pressing down more or less on the button eo.

The button 50 may beprovided with a bayonet slot to coperate with a pinso that it can be retained in its lowered position when it is desired toplay with theV full electro-magnetic effect. The buttons are preferablyplaced on the front ledge of the piano casing on which the devicesfor-controlling the operation of the pneumatic mechanism are ,alsousually arranged.

llhen the instrument 'isv'to be played manually, these buttons arecommonly covered by the fall lboard of the casing and theelectro-magnetic effect is then controlled by means of the pedal 63, theoperation of which controls the shunt circuit and also moves the hammerres't rail away from the wires permitting the hammers to move backwardso that they will have an extended sweep or blow, whereby the increasein the electro-magnetic eiect will be correlated with the increase ofthe hammer blow. |The link 62 which engages the pin 64 is slotted andconstitutes a lost motion connection, permitting the cylinder 51 to beoperated by the button independently of the pedal 63.

By the arrangements described, the electric mechanism ishoused in thepiano casing the button 50 It will be understood that` in position tocoperate with the strings and instrumentalities therein without addingto the size of the casing and without effecting said mechanism. All thatis necessary is to provide a suitable source of electrical energy forthe conductors 17 and 20, which conductors may be led to a source ofelectricity outside of the piano if desired.

By operating the hammers very lightly, sounds can be produced resemblinginefi'ect organ playing, as the electro-magnetic effect will overpowerthe hammer effect and indeed in this operation, as the hammer rail 56 isnot retracted, the hammers can be operated so lightly that the ordinaryhammer eect will be entirely eliminated. During such operation theelectro-magnetic effect may be intensified if desired by depressing tocut out the shunt circuit.

Again, by proper use of the button 60', the instrument can be playedwith a combination hammer and electro-magnetic effect, something like anorgan and piano combined, and the loudness or softness of thiscombination can be varied in a correlated manner. When the button 60 ispressed down to increase the electro-magnetic effect, the hammer rail 56is retracted t0 increase the hammer effect. Also a swell in theelectro-magnetic or organ effect can be obtained by manipulating thebuttons after the hammers have struck, and by opening the switch 18, theinstrument may be played entirely with a hammer effect. Thus by suitablymanipulating the pedals and buttons, Very remarkable and novel effectsmay be obtained.

The above mechanism for controlling the electromagnetic action can alsobeapplied to pianos having a hammer rest rail made in a plurality ofsections and when this is done, l prefer to use separate and controllingmechanism of the nature above described, for each section of thehammers, as defined by the sections of the hammer rest rail.

rlhe details and arrangements herein shown and described may be greatlyVaried by a skilled mechanic without departing from the scope of myinvention as expressed in the claims.

. r1`herefore, having described my invention, what 1 desire to secure byLetters Patent 1s 1. 1n a piano, the combination of the strings, keysand hammers, means controlled by a note-sheet for operating the hammersautomatically independently of the keys, electro-magnetic mechanism forvibrating the strings, and connections between the hammer-operatingmechanism and the electro-magnetic mechanism whereby when a hammer isoperated either manually or automatically its string will be yibrated bythe electro-magnetic mechanism.

` 2. 1n a piano, 'the combination of the from the hammer operating meansand eiective, when a hammer is operated either manually orautomatically, to energize the magnet coperating with the correspondingstring.

3. In a piano, the combination of the strings and hammer actions,pneumatics con trolled by a note-sheet for operating the ac.

tions automatically, a set of electro-magnets for vibrating the strings,and circuit controlling devices therefor operated from the labstracts ofthe hammer actions.

4. In a piano, the combination of the strings, keys and hammer actions,means controlled by a note sheet for operating the actions independentlyof the keys, a set vof electro-magnets for vibrating the strings, acircuit including said magnets, and devices effective to control the ioWof current through said circuit whereby the piano may be playedautomatically by the hammer actions only or With an electro-magneticeffect in addition thereto.

5. In a piano, the combination of the strings and hammer actions, keysfor operating the actions, means controlled by a note sheet foroperating the actions automatically, electro-magnetic means forvibrating the strings, a circuit including said electromagnetic means,and devices for controlling the flow of electricity in said circuit,thereby permitting the piano to be played either manually orautomatically by the hammer actions only when the circuit is open orwith a combined hammer and electro-'magnetic effect When the circuit isclosed.

6. In a piano, the combination of the strings, keys and hammer actions,a set of electromagnets for` vibrating the strings, a circuit includingsaid electromagnets, and

devices for controlling the `flow of electricity in said circuit, saidparts being so connected that the piano can be played with a combinationhammer and electro-magnetic ciect,

and means independent of the keys for ini I creasing or decreasing theintensity of the hammer and electro-magnetic effect simultaneously.

7. Inga piano, the combination of the strings, keysy and hammer actions,means controlled by a note sheet for operating the actionsautomatically, a set of electromagnetsfor vibratingthe stringsa circuitin-,. cludmg said electromagnets, devices for controlling the flow ofcurrent in said circuit, Vsaid part'sbeing so connected that the pianocan be played with a combination hammer and electro-magnetic effect, andmeans inde-V pendent of the keys by which the intensity of the hammerstroke and of the electromagnetic eliect can be increased or decreased.

8. In a piano, the combination of the strings and hammer actions, keysfor operating the hammer actions, means controlled by a` note sheet foroperating the actions automatically, a set of electromagnets forvibrating the strings, a ciruit including said electromagnets, devicesfor controlling the flow of current in said circuit, said parts anddevices being eiiective' to permit the piano to be played eithermanually or automatically With a combined hammer and electro-magneticeffect, and means independent of the keys effective to increase ordecrease the intensity of the hammer stroke and of the electro-magneticeffect simultaneously.

9. In a piano, the combination of the strings and hammer actions, asetof electromagnets for vibrating the strings, a main circuit including asource of electricity, a branch circuit for each of said electromagnets,a shunt circuit for each branch circuit connected in paralllel With-eachbranch vcircuit andei'ective when closed to reduce the current flowingthrough the branch circuit, and circuit closing devices e'ective, whenthe hammer isloperated, to close the branch circuit through thecorresponding magnet and the shunt circuit in parallel with said branchcircuit successively, Whereby the magnet Will trolled.

10. In a piano, the combination of the strings and hammer actions, a setof electromagnets for vvibrating the strings, 'a main circuit includinga source of electric- `ity, a branch circuit for each of said elec-V,tromagnets for vibrating the strings, a main circuit including a sourceof electricity, a branch circuit for each of said electromagnets, ashunt circuit for each branch circuit connected in parallel With eachbranch circuit and effective When closed to reduce be energized andconthe currentJ flowing through the branch circuit, circuit closingdevices effective when a hammer is operated to close the branch'.

circuit through the corresponding magnet and the shunt circuit inparallel with said branch circuit successively, whereby the magnet willbe energized, and means for varying the resistance in the shunt circuit.

12. In a piano, the combination of the strings and hammer actions, a setof electromagnets for vibrating the strings, a main circuit including asource of electricity, a branch circuit for each of said electromagnets,a shunt circuit for each branch' circuit connectedin parallel with eachbranch circuit and edective when closed to reduce the current flowingthrough the branch circuit, circuit closing devices 'edective when ahammer is operated to close the branch circuit through the correspondingmagnet and the shunt circuit in parallel with said branch circuitsuccessively, vwhereby the magnet will be energized, and means forbreaking the shunt circuit and for varying the resistance therein.

13. In a piano, the combination of thel strings and hammer actions, aset of electromagnets for vibrating the strings, a main circuitincluding a source of electricity, a branch circuit for each of saidelectromagnets, a shunt circuit for each branch circuit connected inparallel with each branch lcircuit and effective when closed to reducethe current flowing through .the branch circuit, circuit closing deviceseffective when a hammer is operated to close the branch circuit throughthe corresponding magnet and the shunt circuit in parallel with saidbranch circuit successively, whereby the .magnet will be energized, amovable bridge arranged in said shunt circuit, a series of contactscoperating therewith, resistances arranged between said Contacts, andmeans for movingsaid bridge whereby the resistance of the shuntcircuitmay be varied.

' 14. In a piano, the combination of the strings and hammer actions, aset of electromagnets for vibrating the strings, a main circuitincluding a source of electricity, a

branch circuit for each of said electromag-- nets, a shunt circuit foreach branch circuit connected in parallel with each branch circuit andeffective when closed to reduce the current flowing through the branchcircuit, circuit closing devices eective when a hammer is operated toclose the branch circuit through the corresponding magnet and the shuntcircuit in parallel with said branch circuit successively, whereby themagnet will be energized, a movable bridge arranged in said shuntcircuit, a series of contacts cooperating therewith, resistancesarrangedbetween said contacts, means for moving said bridge whereby theresistance of the shunt circuit may be varied, and means for moving thecontacts away from the bridge to break the shunt circuit.

15. In a piano, the combination of the current flowing through saidbranch circuit,

and circuit controlling devices effective to control the flow ofcurrentin the shunt circuit and also connected to vary the intensity of thestroke of the hammer actions.

16. In a piano, the combination of the.,

strings and yhammer actions, a set of electro.

magnets for vibrating the strings, a main circuit including a source ofelectricity, a branch circuit foreach of said electromagnets, a shuntcircuit for each branch circuit connected in parallel with said branchcircuit and effective when closed to reduce the current flowing throughsaid branch circuit, and circuit controlling devices effective tocontrol the flow of current in the shunt circuit andalso connected tovary the intensity of the stroke of the hammer actions simultaneouslywith variations in the flow of current in the shunt circuit.

17. In a piano, the combination of the strings and hammer actions, keysfor operating the hammer actions, means controlled by a note sheet foroperating the hammers automatically, a set of electromagnets forvibrating the strings, a main circuit including a source of electricity,a branch circuit for each of said electromagnets, a shunt circuit foreach branch circuit connected in parallel with -said branch circuit andeffective when closed to reduce the current flowing through said branchcircuit, and circuit controlling devices elective to vary the intensityof the stroke of the hammer actions .and the effect ofthe-electromagnets simultaneouslywhile the piano is being played eithermanually or automatically.

18. In a piano, the combination of the strings and hammer actions, keysfor' operating the hammer actions, means controlled by a note sheet foroperating the-hammers automatically, a set of electromagnets forvibrating the strings, a main circuit including a source of electricity,a vbranch circuit for each of said electromagnets, a shunt circuit foreach branch circuit connected in parallel with said branch circuit andeffective when closed to reduce the current flowing through said branchcircuit, and circuit controlling devices eective to vary the intensityof the strokey of the hammer actions and the effect of theelectromagnets simultaneously while the piano is being played eithermanually or automatically, said devices including a button connected andeeective to change the resistance of the shunt circuit and to vary theposition of the hammers when the instrument is played automatically, anda pedal connected and effective to vary the position of theham- -mersand to change the resistance of the shunt circuit when the instrument isplayed. manually.

19. In a iano, the combination of the 'strings and ammer actions, keysfor operating the hammer actions, means controlled by a note sheet foroperatingv the hammers automatically, a set of electromagnets forvibrating the strings, a main circuit including a source of electricity,a branch circuit for each of said electromagnets, a shunt circuitconnected in parallel with said branch circuits and effective whenclosed to reduce the flow of current flowing through the branch circuit,circuit controlling devices effective to close one branch circuit andthe correspondingl shunt circuit to energize one of said magnets when ahammer is operated, and means elective to control the flow of currentthrough the shunt circuit after the hammer has been operated therebyproducing a varying electromagnetic ei'ect.

20. In a piano, the combination of the strings and hammer actions, a setof electromagnetsfor vibrating the strings, a set of pulsatorsmechanically connected to the strings and each electrically connected inVseries with one of said electromagnets, a

main circuit including a source of electrlcity, a branch circuit foreach electromagnet and associated pulsator, a shunt circuit for eachbranch circuit connected in parallel with said magnet and effective whenclosed to reduce the currentI flowing through said magnet, and circuitclosing devices effective when a hammer is operated to close the branchcircuit through the corresponding magnet and pulsator and also toclosethe associated shunt circuit, whereby the magnet will be energizedandthe pulsator -opf erated.

2l. In a piano, the combination ofv the strings and hammer actions, aset of electromagnets for vibrating the strings, a set of pulsatorsmechanically connected to the strings and each electrically connected inseries with one of said electromagnets, a main circuit including asourceof electricity, a branch circuit for each electromagnet and associatedpulsator, a shunt circuit for each branch circuit, connected linparallel with said magnet and 'eective when closed to reduce the currentiowing through said magnet, circuit closing devices effective when ahammer is operated to close the branch circuit through the correspondingmagnet and pulsator and also to close the associated shunt circuit,whereby the magnet will be energized and the pulsator operated,and'means effective to break the shunt circuit, l

22. In a piano, the combination of the strings and hammer actions, a setof electromagnets for vibrating the strings, a set of pulsatorsmechanically connected to theV strings and eachelectrically connected inseries with one of said electromagnets, a

main circuit including a source of electricity, a branch circuit foreach electromagnet and associated pulsator, a shunt circuit for eachbranch circuit connected in parallel with said magnet and effective whenclosed'to reduce the current fiowing through said magnet, circuitclosing devices f effective when a hammer is operated to close thebranch circuit through the correspondingmagnet and pulsator and also toclose the associated shunt circuit, whereby the magnet will be energizedand the pulsator operated, and means effective to vary the resistance inthe shunt circuit.

23. In a piano, the combination of the strings and 'hammer actions, aset of electroeffective when a hammeris operated to close the branchcircuit through the correspondp ing magnet and pulsator and also toclose the associated shunt circuit, whereby the magnet will be energizedandthe pulsator operated, and means effective to break the shunt circuitor to vary the resistance therein.

24. In a piano, the combination of the strings and hammer actions, a setof electromagnets for vibrating the strings, a main circuit including asource of. electricity, a

branch circuit for each of said electromag- 7 nets, a shunt circuit Jfor"each branch circuit connected in parallel therewith and eilective whenclosed to reduce. the current flowing through the branch circuit, andcircuit closing devices effective when a hammer is op- 1 erated to firstcomplete the branch circuit through the corresponding magnet to therebyenergize the magnet and to thereafter close the corresponding shuntcircuit.

25. In a piano, the combination of the strings and hammer actions, a setof electromagnets and pulsators for vibrating thestrings, a main circuitincluding a source of electricity, a branch circuit for eachelectromagnet and associated pulsator, a shunt circuit for each branchcircuit connectedvin parallel with said magnet and effective when closedto reduce the current iowing through finali-,sia

10 casing, Within which rail said magnets are embedded in an insulatingmaterial forming therein a substantially unitary structure.

ln testimony whereof l have hereunto set myha-nd7 in the presence of twosubscribing Witnesses.

GEORGE BREED.

Witnesses:

W. E. RAMMELKAMP, ROBERT L. STOTESBURY.

